Initialise clocks, use cortex_m::Delay

src/main.rs

@@ -8,36 +8,61 @@ use cortex_m_rt::entry;
 use defmt::*;
 use defmt_rtt as _;
 use embedded_hal::digital::v2::OutputPin;
-use hal::pac;
-use hal::sio::Sio;
+use embedded_time::fixed_point::FixedPoint;
 use panic_probe as _;
 use rp2040_hal as hal;
 
+use hal::{
+    clocks::{init_clocks_and_plls, Clock},
+    pac,
+    sio::Sio,
+    watchdog::Watchdog,
+};
+
 #[link_section = ".boot2"]
 #[used]
 pub static BOOT2: [u8; 256] = rp2040_boot2::BOOT_LOADER;
 
 #[entry]
 fn main() -> ! {
+    info!("Program start");
     let mut pac = pac::Peripherals::take().unwrap();
-
-    info!("Hello World!");
+    let core = pac::CorePeripherals::take().unwrap();
+    let mut watchdog = Watchdog::new(pac.WATCHDOG);
     let sio = Sio::new(pac.SIO);
+
+    // External high-speed crystal on the pico board is 12Mhz
+    let external_xtal_freq_hz = 12_000_000u32;
+    let clocks = init_clocks_and_plls(
+        external_xtal_freq_hz,
+        pac.XOSC,
+        pac.CLOCKS,
+        pac.PLL_SYS,
+        pac.PLL_USB,
+        &mut pac.RESETS,
+        &mut watchdog,
+    )
+    .ok()
+    .unwrap();
+
+    let mut delay = cortex_m::delay::Delay::new(core.SYST, clocks.system_clock.freq().integer());
+
     let pins = hal::gpio::Pins::new(
         pac.IO_BANK0,
         pac.PADS_BANK0,
         sio.gpio_bank0,
         &mut pac.RESETS,
     );
+
     let mut led_pin = pins.gpio25.into_push_pull_output();
 
     loop {
         info!("on!");
         led_pin.set_high().unwrap();
         // TODO: Replace with proper 1s delays once we have clocks working
-        cortex_m::asm::delay(500_000);
+        delay.delay_ms(500);
         info!("off!");
         led_pin.set_low().unwrap();
-        cortex_m::asm::delay(500_000);
+        delay.delay_ms(500);
     }
 }